Machining, Measurement, and Control Laboratory

High Speed, High Productive Drilling and Tapping by Intelligent Machine Tools
- Prevention of Tool Breakage and Monitoring of Tool Failure for Difficult-to-cut Materials -

Yoshinori Yamaoka (Yamazaki Mazak Corp.)
Yoshiaki Kakino (Kyoto University)
Makoto Fujishima (Mori Seiki Co., Ltd.)

This paper presents a method of real-time adaptive control of drilling and tapping for the difficult-to-cut material such as superheat resistant alloy (Inconel 718). Real-time adaptive control such as adaptive pecking is effective for these materials. In tapping processes, normally adaptive control has disadvantage to be applied because C axis requires high acceleration in the process. In general, conservative cutting speed is applied to such difficult-to-cut materials, since high cutting speed intense tool wear. Moreover, only in the case with low cutting speed, C-axis is able to be operated with high acceleration to stop its rotation. By introducing adaptive control, chip jamming is avoided during drilling and tapping processes.

Keywords:   Intelligent machine tools, drilling, tapping, adaptive control, difficult-to-cut material.